Fluid handling devices are becoming increasingly popular, and there is an increased demand for fluid handling devices that are both portable and easy to use. Portable fluid handling devices are used in applications such as home care, point of care testing, fuel cells, fragrance dispensers, etc. In order for a portable fluid handling device to be effective and efficient, it should be lightweight, small in size, consume minimal power, operate with low noise, and be cost effective to manufacture. In many applications, it is also important that the fluid handling device provide an accurate and consistent fluid distribution. Therefore, it is preferable to incorporate an efficient fluid valve in the fluid handling device. In many aspects, the fluid valve characterizes the device's efficiency.
One example of a portable valve that attempts to meet the above criteria is a miniature solenoid valve. The miniature solenoid valve however, is not always effective as required by certain implementations. Solenoid valves are typically limited in size, and in order to obtain adequate performance, a solenoid valve typically consumes a substantial amount of power. The power consumption of a solenoid valve, in some circumstances, is unacceptable, especially when using batteries as a power source, for example. The batteries may not be able to provide power to the valve for a sufficient length of time. Furthermore, in some applications, it may be desirable to retain the valve in a specific open or mid-point position. If this position requires continuous actuation of the solenoid, the valve will likely consume a substantial amount of power thereby increasing the cost associated with operating the valve.
Another prior art solution has been the use of electrically actuated piezo valves. Some piezo valves operate using a closing arm that seals against a sealing shoulder when the piezo element is de-activated. These valves typically require a substantial amount of space to operate and may not always provide an adequate solution, as they are subject to clogging when used with liquids that may dry around the orifice.
Another existing solution has been the use of shape memory alloys that transform shape and/or size when heated. Shape Memory Alloy (SMA) actuated valves provide an advantage over the previously mentioned prior art solutions as they can typically be manufactured smaller and generally consume less power. However, many fluid handling devices are applied to situations in which a fast response time is required. Shape memory alloy (SMA) actuated valves can have a slow response time, due to the necessary heating and cooling times to transition between the two states of the SMA element. To compete with traditional technologies, SMA actuated valves should cover all the applications and functions required by a user, while maintaining a high level of performance. The present invention provides a versatile, common architecture which addresses the aforementioned problems.